SUMMERFIELD, G. e. (1971). English in practice secondary English departments: At work ed. C.U.P.
Chicago-čujuhus (17. p.)SUMMERFIELD, Geoffrey ed. English in Practice Secondary English Departments: At Work Ed. London: C.U.P, 1971.
MLA-čujuhus (9. p.)SUMMERFIELD, Geoffrey ed. English in Practice Secondary English Departments: At Work Ed. C.U.P, 1971.
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